Consumer packages for milk, juice and other drinks are available in a multiplicity of different types and sizes, e.g. parallelepipedic packages produced from paper/plastic laminate, blow moulded bottle or beaker-shaped packages of whole plastic material, as well as different types of packaging containers of glass, sheet metal or aluminium. A plurality of these different packaging types include some form of opening arrangement in order to facilitate consumer access to the contents of the package for pouring into drinking vessels or for consumption direct from the packaging container. In packages of bottle type, some form of screw cap is a common solution, while packaging containers of plastic or paper/plastic laminate often include a simple tear indication or a prefabricated pouring aperture which is covered by a tear-off strip, a so-called pull-tab. Separately manufactured opening arrangements of thermoplastic material, for example injection moulded opening arrangements with a pouring spout or a short neck and a snap- or screw cap are also known in the art. Such types of opening arrangements may be injection moulded in situ, i.e. around an opening punched out in the material, so that this is closed and sealed until the consumer opens the opening arrangement. Naturally, injection moulded opening arrangements may also be of different sizes and even cover an entire upper surface panel of a packaging container, in which event they also function as an end wall to the packaging container.
In particular in opening arrangements of the above-mentioned, injection moulded type, it is usual to seal the pouring aperture with some form of tear-off membrane which, on the one hand, ensures that the opening arrangement is completely tight prior to being opened, and, on the other hand, indicates that the package has not previously been opened (tamper-proof). The membrane is often also used in that type of opening arrangement which has a screw or snap-cap for reclosure. In order to make for tearing off of the membrane, this is defined from surrounding parts of the opening arrangement or surrounding parts of the packaging container proper by means of a weakening line which makes it possible to separate the membrane and remove it. In order to facilitate this operation, the membrane is often provided with some form of gripping device or pulling device which makes it possible for the consumer to get a steady grip such that, in particular, the initiation of the tearing operation along the weakening line is facilitated. Initiation of the tearing operation may occasionally cause difficulties (in particular for certain consumers), since the weakening line, despite its obvious, weakening purpose, must not weaken the material to such an extent that rupture and leakage occur. Earlier attempts to obviate the difficulties in the initiation of the tearing off operation have been essentially based on the concept of minimising the necessary force required by ensuring that the weakening line leaves a minimum of residual material thickness, but since tolerances in production are relatively great, a relatively large material thickness must nevertheless be left in order to ensure that leakage does not occur. Other possibilities for facilitating the initiation of the tearing off operation are, naturally, to provide the gripping device with a powerful pull ring or corresponding gripper which makes it possible for the consumer to transmit extreme tractive force to the membrane on the initiation of the tearing operation. This provision is not, however, possible in several types of opening arrangements, for example the type of opening arrangement which includes a short, lidded neck in which the membrane and gripping member are to be accommodated.
There is thus a general need in the art to realise an opening arrangement of the above-outlined type in which the initiation of the tearing off of the membrane is facilitated without any of the above-considered drawbacks occurring.